The Basidia of Exidia nucleata. I. Ultrastructure

Abstract

The ultrastructure of KMnO4-fixed basidia and sub-basidial septa of E. nucleata (Heterobasidiomycetidae) are described and illustrated. The basidia contain mitochondria with plate-like cristae, vacuoles, 2 types of unidentified cytoplasmic inclusions, oil globules, and systems of parallel, double lamellae. The endoplasmic reticulum is connected to the outer membrane of the alveolate nuclear envelope but not to the ectoplast or cytoplasmic organelles other than the nucleus. The sub-basidial septa are similar to those reported in other Basidiomycetes. The pore becomes occluded. following the collapse of the basidium, by the formation of secondary wall material.